Automated transfer systems are utilized by parcel delivery companies and airports to match in-coming packages with proper outgoing transport headed for the packages' destinations. The sorting equipment must be very fast, yet provide gentle and accurate handling of packages of various dimensions, shapes, and sizes.
Slide sorters utilize a pop-up conveyor or transfer mechanism to lift and carry selected articles, parcels, packages; bags to another conveyor oriented in a different direction and are often used in pallet handling, mail tray handling, or the like. With wooden pallets chains are often used as the conveying surface whereas with trays or boxes belts, rollers, wheels, and/or flexible material comprise the conveying surface. The pop-up conveyor is only activated upon its control system sensing by weight, photo cell, infrared, laser, or other electronic or radiation detecting device an article moving toward it from a feed conveyor. The pop-up conveyor than raises above the surface level of the on-coming conveyor as the article passes thereover, to lift the article or portion thereof and support same on a conveyor means to transfer the article to a different conveyor or other article removing device. The pop-up conveyor typically remains inactive until the sensors sense an article on the feed conveyor in on or in close proximity to the pop-up conveyor whereby the conveyor is activated raising and engaging a belt, roller, chain drive or combinations thereof to contact the bottom surface of the article and push it at a selected angle, usually 90 degrees off of the on-coming feed conveyor.
Meeting this goal is particularly difficult in the case of large or heavy irregular shaped packages. Belt and roller conveyor systems have often been used in package sorting systems to move packages from in-coming loading docks to outgoing transport. An initial sorting of packages traveling along a conveyor may be accomplished by diverting packages from the conveyor based on their destinations, or based on their size, weight or other characteristics.
Some conveyor systems include a main conveyor having a belt or multiple powered rollers or wheels fitted between the wheels below the normal conveyor surface. U.S. Pat. No. 3,926,298 shows a conveyor assembly wherein a section of the drive rollers can be lowered to drop a parcel onto the belt conveyor, without interrupting the speed of articles moving along the primary path. However, the belt conveyor can divert in only one direction.
U.S. Pat. No. 5,547,084 shows a luggage sorting system in which bags are fed onto a moving carriage that includes multiple conveyors. After loading, the carriage moves along a track until it aligns with output conveyors. Then the carriage conveyors shift the bags from the carriage to appropriate output conveyors. This is not a high speed sorting system because the bags must come to rest on the carriage and be transported laterally, and then accelerated again after sorting.
There is a need in the art for a diverter that can reliably divert irregular shaped packages from a main conveyor path, using a slide sorter mechanism that is modular and easy to repair, all while operating at a high speed of throughput along the main path.
Conventional pop-up transfer conveyors require that the on-coming conveyor belt stop as the article passes over the pop-up transfer conveyor in order that the belts of the pop of conveyor can be raised and activated to transfer the article onto a receiving or diverging conveyor with the article maintained in a proper orientation for conveyance on the receiving conveyor. A problem occurs when the oncoming conveyor does not stop with the article over the pop-up conveyor, in that longitudinal articles are rotated sideways in the transfer procedure which causes downstream orientation problems with the receiving conveyor.